fix: history rows show the ISO datetime and the age (closes #760)

Home, AddressDetail and AddressToken showed only the relative age, with
the datetime as a tooltip. Each row now shows the datetime and then the
age in parentheses, on a line of its own, through transactionTimeHtml()
in helpers.js, which TransactionDetail also uses. The direction label
moves to its own right-aligned line below.

Model: opus-5-5

README.md

@@ -264,6 +264,8 @@ The shared modules, each in one line:
   messaging, windows and the lock.
 - `buildInfo.js`: the version, license, author, commit and date compiled into
   About.
+- `calldataDecoder.js`: the ERC-20 `approve()` and `transfer()` decoder, which
+  hands other calldata to `uniswap.js`. Popup only.
 - `chainSwitch.js`: the popup's network switch.
 - `chainSwitchFields.js`: the fields a network switch changes.
 - `constants.js`: `DEBUG`, the default endpoints, the ERC-20 ABI and the burn
@@ -1189,15 +1191,23 @@ These helpers write one kind of value on every screen that shows it:
 
 Most screens show token and ETH amounts with four decimal places. History rows
 cut amounts to four decimals and never round up (`truncateAmount()` in
-`src/shared/amountDisplay.js`). The balance lists and Home's ETH balance round
+`src/shared/amountDisplay.js`). These balances are cut the same way:
-to four places. The screens that state what is being authorized cut as the
+
-history does, and extend an amount below 0.0001 to its first nonzero digit
+- the balance lists;
+- Home's ETH balance;
+- Send's current balance;
+- ConfirmTx's balance line.
+
+So a balance below 0.0001 reads `0.0000` there.
+
+The screens that state what is being authorized cut as the history does, and
+extend an amount below 0.0001 to its first nonzero digit
 (`truncateAmountNeverZero()`). So a nonzero amount never reads as zero there.
 Those screens are:
 
 - TxApproval;
 - SignApproval's Permit warning;
-- ConfirmTx, and Send's current balance;
+- ConfirmTx's amount and network fee;
 - WaitTx, SuccessTx and ErrorTx.
 
 TransactionDetail shows the exact amount and its base units.
@@ -1264,9 +1274,8 @@ A native amount is labelled with the native currency of the transaction's chain:
 `src/shared/networks.js`). The balance lists and Send use the active network's.
 The decoded swap lines call the native currency `ETH` on both networks.
 
-TransactionDetail shows the time as an ISO datetime and a relative age. A
+TransactionDetail and every history row show the time as an ISO datetime and
-history row shows the age, with the datetime as its tooltip. With "UTC
+then a relative age. With "UTC Timestamps" on, the datetime is in UTC.
-Timestamps" on, the datetime is in UTC.
 
 Every nonzero holding is stored exactly. A token holding below 0.000001 is left
 out of:
@@ -1379,7 +1388,7 @@ approval screens show a red warning.
 ### Transaction decoding
 
 TxApproval and TransactionDetail try to decode calldata into a summary
-(`decodeCalldata()` in `src/popup/views/approval.js`). SuccessTx repeats
+(`decodeCalldata()` in `src/shared/calldataDecoder.js`). SuccessTx repeats
 TxApproval's summary. Decoding is a display aid. When it fails, the raw calldata
 is shown in full. No contract gets any treatment beyond a legible confirmation
 screen.
@@ -1645,11 +1654,10 @@ The development dependencies ship nowhere:
 
 ### Crypto policy
 
-Hashing, key derivation, signing and encryption go through `ethers` or
+In the extension, hashing, key derivation, signing and encryption go through
-`libsodium-wrappers-sumo`. No primitive is implemented in this repository. A new
+`ethers` or `libsodium-wrappers-sumo`. A new recovery phrase takes its random
-recovery phrase draws its random bytes from the browser's
+bytes from `ethers`. `build.js` and `script/lib/package.js` also hash files with
-`crypto.getRandomValues()`. The build tooling, `build.js` and `script/lib/`,
+`ethers`. No primitive is implemented in this repository.
-hashes files with Node's `crypto`; none of it ships in the extension.
 
 ### Content Security Policy
 

RULES.md

@@ -108,10 +108,7 @@ contradicts either, the originals govern.
 - [ ] All tool invocations via `make` targets, never directly
 - [ ] `make check` = `make test` + `make lint` + `make fmt-check`
 - [ ] `main` always passes `make check`
-- [ ] Branch per issue, cut from `next`. One PR per issue, based on `next`,
+- [ ] Feature branches for all changes, merge to main when done
-      squash-merged into `next` on a passed independent review. `main` is
-      reached only by the per-milestone PR from `next`; releases are tagged from
-      `main`. `next` and `main` must stay green; feature branches may be red.
 - [ ] No force-push to `main`
 - [ ] Pre-commit hook runs `make check`
 

build.js

@@ -1,8 +1,8 @@
 const fs = require("fs");
 const path = require("path");
-const crypto = require("crypto");
 const { execSync } = require("child_process");
 const esbuild = require("esbuild");
+const { sha256 } = require("ethers");
 const { resolveVersion } = require("./script/lib/version");
 const {
     BACKGROUND_ENTRY_PREFIX,
@@ -314,10 +314,8 @@ function copyIcons(distDir) {
 }
 
 function sha256File(absPath) {
-    return crypto
+    // ethers prefixes the hex with 0x; the receipt holds bare hex.
-        .createHash("sha256")
+    return sha256(fs.readFileSync(absPath)).slice(2);
-        .update(fs.readFileSync(absPath))
-        .digest("hex");
 }
 
 // Write the receipt for the files this build emitted. Deliberately records no

script/lib/package.js

@@ -25,9 +25,9 @@
 
 "use strict";
 
-const crypto = require("crypto");
 const fs = require("fs");
 const path = require("path");
+const ethers = require("ethers");
 
 const { readZip, writeZip } = require("./zip");
 const { resolveVersion } = require("./version");
@@ -60,8 +60,9 @@ function fail(message) {
     throw new Error(message);
 }
 
+// Lowercase hex without the 0x prefix ethers adds, as sha256sum prints it.
 function sha256(buf) {
-    return crypto.createHash("sha256").update(buf).digest("hex");
+    return ethers.sha256(buf).slice(2);
 }
 
 // Every regular file under dir, as archive-root-relative forward-slashed
@@ -291,4 +292,9 @@ if (require.main === module) {
     }
 }
 
-module.exports = { checkSelfContained, htmlReferences, manifestReferences };
+module.exports = {
+    checkSelfContained,
+    htmlReferences,
+    manifestReferences,
+    sha256,
+};

src/popup/views/addressDetail.js

@@ -12,8 +12,7 @@ const {
     attachCopyHandlers,
     goBack,
     pushCurrentView,
-    isoDate,
+    transactionTimeHtml,
-    timeAgo,
 } = require("./helpers");
 const { state, saveState, currentNetwork } = require("../../shared/state");
 const { formatAddressTotal, getAddressValue } = require("../../shared/prices");
@@ -236,10 +235,11 @@ function renderTransactions(txs) {
         const nameStr = escapeHtml(title || ensName || "");
         const err = tx.isError ? " (failed)" : "";
         const opacity = tx.isError ? " opacity-50" : "";
-        const ago = escapeHtml(timeAgo(tx.timestamp));
-        const iso = escapeHtml(isoDate(tx.timestamp));
         html += `<div class="tx-row py-2 border-b border-border-light text-xs cursor-pointer hover:bg-hover${opacity}" data-tx="${i}">`;
-        html += `<div class="flex justify-between"><span class="text-muted" title="${iso}">${ago}</span><span>${dirLabel}${err}</span></div>`;
+        // The time has a line of its own, so a long time or direction label
+        // never pushes the other onto a second line.
+        html += `<div class="text-muted">${transactionTimeHtml(tx.timestamp)}</div>`;
+        html += `<div class="text-right">${dirLabel}${err}</div>`;
         html += txCounterpartyHtml(counterparty, nameStr, amountStr);
         html += `</div>`;
         i++;

src/popup/views/addressToken.js

@@ -18,8 +18,7 @@ const {
     attachCopyHandlers,
     goBack,
     pushCurrentView,
-    isoDate,
+    transactionTimeHtml,
-    timeAgo,
 } = require("./helpers");
 const { state, saveState, currentNetwork } = require("../../shared/state");
 const { bundledToken, resolveSymbol } = require("../../shared/tokenList");
@@ -159,10 +158,10 @@ function renderBalance() {
     const addr =
         state.wallets[state.selectedWallet].addresses[state.selectedAddress];
     const tokenId = state.selectedToken;
-    let amount, price;
+    let balance, price;
     if (tokenId === "ETH") {
         // null when no refresh has read the balance.
-        amount = unknownableAmount(addr.balance);
+        balance = addr.balance;
         price = getPrice("ETH");
     } else {
         const id = tokenId.toLowerCase();
@@ -175,12 +174,13 @@ function renderBalance() {
         // null when the scale is unknown, or when no refresh has read the
         // token's balance: no quantity to show, and none to price.
         // balanceLine() states that rather than printing 0.0000.
-        if (tb) amount = unknownableAmount(tb.balance);
+        if (tb) balance = tb.balance;
-        else amount = tracked && tracked.balanceNotFetched ? null : 0;
+        else balance = tracked && tracked.balanceNotFetched ? null : "0";
         price = getPrice(tokenId);
     }
 
     // USD total for this token only
+    const amount = unknownableAmount(balance);
     const usdVal = price && amount !== null ? amount * price : null;
     const usdStr = formatUsd(usdVal);
     $("address-token-usd-total").innerHTML = escapeHtml(usdStr) || " ";
@@ -188,7 +188,7 @@ function renderBalance() {
     // Single token balance line (no tokenId — not clickable here)
     $("address-token-balance").innerHTML = balanceLine(
         currentSymbol,
-        amount,
+        balance,
         price,
     );
 }
@@ -328,10 +328,11 @@ function renderTransactions(txs) {
         const nameStr = escapeHtml(title || ensName || "");
         const err = tx.isError ? " (failed)" : "";
         const opacity = tx.isError ? " opacity-50" : "";
-        const ago = escapeHtml(timeAgo(tx.timestamp));
-        const iso = escapeHtml(isoDate(tx.timestamp));
         html += `<div class="tx-row py-2 border-b border-border-light text-xs cursor-pointer hover:bg-hover${opacity}" data-tx="${i}">`;
-        html += `<div class="flex justify-between"><span class="text-muted" title="${iso}">${ago}</span><span>${dirLabel}${err}</span></div>`;
+        // The time has a line of its own, so a long time or direction label
+        // never pushes the other onto a second line.
+        html += `<div class="text-muted">${transactionTimeHtml(tx.timestamp)}</div>`;
+        html += `<div class="text-right">${dirLabel}${err}</div>`;
         html += txCounterpartyHtml(counterparty, nameStr, amountStr);
         html += `</div>`;
         i++;

src/popup/views/approval.js

@@ -12,9 +12,13 @@ const {
     formatFee,
     tokenLabel,
     blockscoutOffTokenNoteHtml,
-    tokenSourcesByChainId,
 } = require("./helpers");
-const { state, saveState, currentNetwork } = require("../../shared/state");
+const {
+    state,
+    saveState,
+    currentNetwork,
+    tokenSourcesByChainId,
+} = require("../../shared/state");
 const {
     networkById,
     networkByChainId,
@@ -26,21 +30,24 @@ const {
     getAddress,
     getBigInt,
     getBytes,
-    Interface,
     MaxUint256,
     toUtf8String,
 } = require("ethers");
 const { getPrice, formatUsd } = require("../../shared/prices");
-const { ERC20_ABI } = require("../../shared/constants");
 const { INVISIBLE_CHARACTERS } = require("../../shared/symbolSpoof");
 const {
     resolveTokenDecimals,
     resolveTokenSymbol,
     unknownDecimalsAmount,
 } = require("../../shared/approvalAmount");
+const {
+    decodeCalldata,
+    tokenAmountText,
+} = require("../../shared/calldataDecoder");
 // Four decimals, with the nonzero floor these screens hold: every amount this
 // view renders — the ERC-20 line, the ETH value, the max fee — and every one
-// it carries forward to the wait/success/error screens goes through it.
+// it carries forward to the wait/success/error screens goes through it. The
+// ERC-20 line gets it from tokenAmountText().
 const {
     truncateAmountNeverZero: formatTxValue,
 } = require("../../shared/amountDisplay");
@@ -54,11 +61,8 @@ const {
     typedDataChainRefusal,
 } = require("../../shared/approvalVerify");
 const txStatus = require("./txStatus");
-const uniswap = require("../../shared/uniswap");
 const { runtimeApi, sendMessage } = require("../../shared/browserApi");
 
-const erc20Iface = new Interface(ERC20_ABI);
-
 // The link opens the explorer of the network with `chainId`, or of the active
 // network when none is given. A chain id that names no network has no
 // explorer, so the address is drawn without a link.
@@ -70,141 +74,6 @@ function approvalAddressHtml(address, chainId) {
     return renderAddressHtml(address, { title, chainId });
 }
 
-// The amount line for a decoded ERC-20 call. With a known scale it is the
-// token quantity; with `decimals` null it is the base-unit integer with the
-// unknown scale stated, because formatting it with an assumed scale is what
-// showed a 5,000-token transfer as `0.0000`. `raw` is what the status screens
-// carry, `display` is what the approval screen shows.
-function tokenAmountText(rawAmount, decimals, symbol) {
-    if (decimals === null) {
-        const unknown = unknownDecimalsAmount(rawAmount);
-        return { raw: unknown, display: unknown };
-    }
-    const formatted = formatTxValue(formatUnits(rawAmount, decimals));
-    return {
-        raw: formatted,
-        display: formatted + (symbol ? " " + symbol : ""),
-    };
-}
-
-// Try to decode calldata sent from `fromAddress` to `toAddress` on the network
-// with chain id `chainId`, using known ABIs.
-// Returns { name, description, details } or null.
-function decodeCalldata(data, toAddress, chainId, fromAddress) {
-    if (!data || data === "0x" || data.length < 10) return null;
-
-    // Where a token's name and scale are looked for, for every decoder below:
-    // what the wallet knows of the tokens on the network with `chainId`, which
-    // need not be the active one. The ERC-20 amount line and the swap's Amount
-    // and Min. received lines resolve the scale the same way, and refuse to
-    // format the same way when it is nowhere.
-    const decimalsSources = tokenSourcesByChainId(chainId);
-
-    // Try ERC-20 (approve / transfer)
-    try {
-        const parsed = erc20Iface.parseTransaction({ data });
-        if (parsed) {
-            const tokenSymbol = resolveTokenSymbol(toAddress, decimalsSources);
-            // null when no source knows this token's scale. It is not
-            // defaulted to 18: an amount formatted with a guessed scale is
-            // the wrong number, and for a token with fewer decimals than the
-            // guess it is the wrong number in the direction that reads as
-            // zero. See tokenAmountText().
-            const tokenDecimals = resolveTokenDecimals(
-                toAddress,
-                decimalsSources,
-            );
-            const contractLabel = tokenSymbol
-                ? tokenSymbol + " (" + toAddress + ")"
-                : toAddress;
-
-            if (parsed.name === "approve") {
-                const spender = parsed.args[0];
-                const rawAmount = parsed.args[1];
-                const maxUint = BigInt(
-                    "0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
-                );
-                const isUnlimited = rawAmount === maxUint;
-                // An unbounded allowance needs no scale to describe, so it is
-                // still named rather than refused.
-                const amount = isUnlimited
-                    ? { raw: "Unlimited", display: "Unlimited" }
-                    : tokenAmountText(rawAmount, tokenDecimals, tokenSymbol);
-
-                return {
-                    name: "Token Approval",
-                    description: tokenSymbol
-                        ? "Approve spending of your " + tokenSymbol
-                        : "Approve spending of an ERC-20 token",
-                    details: [
-                        {
-                            label: "Token",
-                            value: contractLabel,
-                            address: toAddress,
-                            isToken: true,
-                        },
-                        {
-                            label: "Spender",
-                            value: spender,
-                            address: spender,
-                        },
-                        {
-                            label: "Amount",
-                            value: amount.display,
-                            rawValue: amount.raw,
-                        },
-                    ],
-                };
-            }
-
-            if (parsed.name === "transfer") {
-                const to = parsed.args[0];
-                const rawAmount = parsed.args[1];
-                const amount = tokenAmountText(
-                    rawAmount,
-                    tokenDecimals,
-                    tokenSymbol,
-                );
-
-                return {
-                    name: "Token Transfer",
-                    description: tokenSymbol
-                        ? "Transfer " + tokenSymbol
-                        : "Transfer ERC-20 token",
-                    details: [
-                        {
-                            label: "Token",
-                            value: contractLabel,
-                            address: toAddress,
-                            isToken: true,
-                        },
-                        { label: "Recipient", value: to, address: to },
-                        {
-                            label: "Amount",
-                            value: amount.display,
-                            rawValue: amount.raw,
-                        },
-                    ],
-                };
-            }
-        }
-    } catch {
-        // Not ERC-20 — fall through
-    }
-
-    // Try Uniswap Universal Router
-    const routerResult = uniswap.decode(
-        data,
-        toAddress,
-        chainId,
-        decimalsSources,
-        fromAddress,
-    );
-    if (routerResult) return routerResult;
-
-    return null;
-}
-
 function showPhishingWarning(elementId, isPhishing) {
     const el = $(elementId);
     if (!el) return;
@@ -1298,7 +1167,6 @@ function init(_ctx) {
 module.exports = {
     init,
     show,
-    decodeCalldata,
     formatTypedDataHtml,
     typedDataRefusal,
 };

src/popup/views/confirmTx.js

@@ -43,9 +43,12 @@ const {
     transferAmountUnits,
 } = require("../../shared/transferAmount");
 const { assertWithinCeilings } = require("../../shared/approvalVerify");
-// The amount, the balance line and the fee reserve go through it, as the
+// The amount and the fee reserve keep the nonzero floor, as the approval
-// approval screen's amounts do.
+// screen's amounts do. The balance line is cut as the balance lists cut it.
-const { truncateAmountNeverZero } = require("../../shared/amountDisplay");
+const {
+    truncateAmount,
+    truncateAmountNeverZero,
+} = require("../../shared/amountDisplay");
 const {
     CODES,
     FEE_PENDING,
@@ -160,7 +163,7 @@ function renderBalance(txInfo) {
     const price = getPrice(txInfo.token, txInfo.chainId);
     const balUsd = price ? parseFloat(bal) * price : null;
     $("confirm-balance").textContent = valueWithUsd(
-        truncateAmountNeverZero(bal) + " " + symbol,
+        truncateAmount(bal) + " " + symbol,
         balUsd,
     );
 }

src/popup/views/deleteAddress.js

@@ -79,8 +79,8 @@ function recoveryPathText(wallet) {
 // "Holds" means ETH or any ERC-20 the wallet knows about — an address with no
 // ETH and a five-figure stablecoin position must not get the blank line on
 // the one screen whose job is to warn. The sentence names no figure of its
-// own: the rendered lines round to four decimals, so a sentence built from a
+// own: the rendered lines cut to four decimals, so a sentence built from their
-// rounded number would report "0.0000 ETH" for an address holding real money.
+// figure would report "0.0000 ETH" for an address holding real money.
 // The lines below it carry the amounts, in the same format as Home and
 // AddressDetail, followed by the USD total when there is one to give — no
 // total line at all on testnet, before the first price fetch or while no

src/popup/views/helpers.js

@@ -18,6 +18,7 @@
 const { formatEther } = require("ethers");
 const makeBlockie = require("ethereum-blockies-base64");
 const {
+    truncateAmount,
     truncateAmountNeverZero,
     isBelowOneMillionth,
 } = require("../../shared/amountDisplay");
@@ -31,7 +32,12 @@ const { escapeHtml } = require("../../shared/html");
 const { isDebug } = require("../../shared/log");
 const { networkByChainId } = require("../../shared/networks");
 const { formatUsd, getPrice } = require("../../shared/prices");
-const { state, saveState, currentNetwork } = require("../../shared/state");
+const {
+    state,
+    saveState,
+    currentNetwork,
+    tokenSourcesByChainId,
+} = require("../../shared/state");
 const { displaySymbol } = require("../../shared/symbolDisplay");
 const { isSpoofedSymbol } = require("../../shared/symbolSpoof");
 const { walletHasRecoveryPhrase } = require("../../shared/wallet");
@@ -305,32 +311,6 @@ function nativeCurrency() {
     return currentNetwork().nativeCurrency;
 }
 
-// What the wallet knows of the tokens on the network with this chain id, or
-// on the active network when no chain id is given, as the `sources` that
-// resolveTokenSymbol() and resolveTokenDecimals() take. A contract address
-// names a token on one network only, and every token balance held is the
-// active network's, so another network gets the tokens tracked on it
-// (state.networkTrackedTokens, see applyChainSwitchFields()) and no balances.
-//
-// The wallets' balances hold what Blockscout reported for each token. So the
-// wallets are returned only while "Use Blockscout" is on.
-function tokenSourcesByChainId(chainId) {
-    const chainIdOrActive = chainId || currentNetwork().chainId;
-    const net = networkByChainId(chainIdOrActive);
-    if (net && net.id === state.networkId) {
-        return {
-            chainId: chainIdOrActive,
-            trackedTokens: state.trackedTokens,
-            wallets: state.useBlockscout ? state.wallets : [],
-        };
-    }
-    return {
-        chainId: chainIdOrActive,
-        trackedTokens: (net && state.networkTrackedTokens[net.id]) || [],
-        wallets: [],
-    };
-}
-
 // The line shown under a token while "Use Blockscout" is off. The token gets
 // the line only when the bundled list and the tracked tokens lack its name or
 // decimals. Otherwise this returns "". The token is a contract address on the
@@ -394,13 +374,15 @@ function formatFee(wei, symbol, chainId) {
 // the row that issue #307 was reported against: every screen that lists a
 // holding renders through here.
 //
-// `amount` is null for a holding whose scale nothing knows
+// `balance` is the stored balance, a decimal string. It is null for a holding
+// whose scale nothing knows
 // (https://git.eeqj.de/sneak/AutistMask/issues/349), and for a balance no
 // refresh has read. There is no quantity to print for it and no fiat value to
-// derive from one, and printing 0.0000 for a real holding is the failure this
+// derive from one. A holding whose amount is unknown is shown as
-// whole rule exists to prevent, so the row says so instead.
+// `quantity unknown` rather than as a zero.
-function balanceLine(symbol, amount, price, tokenId) {
+function balanceLine(symbol, balance, price, tokenId) {
-    const qty = amount === null ? "quantity unknown" : amount.toFixed(4);
+    const amount = unknownableAmount(balance);
+    const qty = amount === null ? "quantity unknown" : truncateAmount(balance);
     const usd =
         price && amount !== null
             ? escapeHtml(formatUsd(amount * price)) || " "
@@ -415,7 +397,7 @@ function balanceLine(symbol, amount, price, tokenId) {
         `<div class="flex text-xs${clickClass}"${tokenAttr}>` +
         `<span class="flex justify-between w-[42ch] max-w-full">` +
         `<span>${escapeHtml(displaySymbol(symbol))}</span>` +
-        `<span>${qty}</span>` +
+        `<span>${escapeHtml(qty)}</span>` +
         `</span>` +
         `<span class="text-right text-muted flex-1">${usd}</span>` +
         `</div>`
@@ -441,7 +423,7 @@ function markTrackedTokensNotFetched() {
 function balanceLinesForAddress(addr, trackedTokens, showZero) {
     let html = balanceLine(
         nativeCurrency(),
-        unknownableAmount(addr.balance),
+        addr.balance,
         getPrice("ETH"),
         "ETH",
     );
@@ -459,7 +441,7 @@ function balanceLinesForAddress(addr, trackedTokens, showZero) {
         if (bal === 0 && !showZero) continue;
         html += balanceLine(
             t.symbol,
-            bal,
+            t.balance,
             getPrice(t.address),
             t.address.toLowerCase(),
         );
@@ -477,7 +459,7 @@ function balanceLinesForAddress(addr, trackedTokens, showZero) {
             }
             html += balanceLine(
                 t.symbol,
-                t.balanceNotFetched ? null : 0,
+                t.balanceNotFetched ? null : "0",
                 getPrice(t.address),
                 t.address.toLowerCase(),
             );
@@ -488,10 +470,10 @@ function balanceLinesForAddress(addr, trackedTokens, showZero) {
 
 // Whether an address holds anything at all: ETH or any ERC-20 the wallet
 // knows about, except a token holding below 0.000001, which the balance list
-// under the remove-address warning leaves out too. Deliberately unrounded —
+// under the remove-address warning leaves out too. Deliberately exact — the
-// the rendered lines round to four decimals, so a dust balance displays as
+// rendered lines cut to four decimals, so a dust balance displays as 0.0000
-// 0.0000 while still being real money at a real address. Callers that warn
+// while still being real money at a real address. Callers that warn about
-// about holdings must ask this, not the rendered figure.
+// holdings must ask this, not the rendered figure.
 function addressHoldsFunds(addr) {
     if (!addr) return false;
     // A null or absent ETH balance reads as unknown, so the address may hold
@@ -633,9 +615,8 @@ function formatAddressHtml(address, ensName, maxLen, title) {
     return renderAddressHtml(address, { title, ensName, maxLen });
 }
 
-// A transaction's time as every screen shows it (README, Amounts): the ISO
+// The ISO datetime of a transaction's time, in UTC when the UTC Timestamps
-// datetime, in UTC when the UTC Timestamps setting is on, and the relative age.
+// setting is on. Views show it through transactionTimeHtml().
-// Views import these two; they keep no copies.
 function isoDate(timestamp) {
     const d = new Date(timestamp * 1000);
     const pad = (n) => String(n).padStart(2, "0");
@@ -692,6 +673,15 @@ function timeAgo(timestamp) {
     return years + " year" + (years !== 1 ? "s" : "") + " ago";
 }
 
+// A transaction's time as every screen shows it (README, Amounts): the ISO
+// datetime, then the relative age in parentheses. With copyable set, the
+// datetime is click-to-copy, and the caller attaches the copy handlers.
+function transactionTimeHtml(timestamp, { copyable = false } = {}) {
+    const iso = isoDate(timestamp);
+    const isoHtml = copyable ? copyableHtml(iso) : escapeHtml(iso);
+    return isoHtml + " (" + escapeHtml(timeAgo(timestamp)) + ")";
+}
+
 // Shared external-link icon SVG used across all views.
 const EXT_ICON =
     `<span class="inline-block w-[10px] h-[10px] ml-[4px] align-middle">` +
@@ -866,7 +856,6 @@ module.exports = {
     keyMaterialName,
     unknownableAmount,
     nativeCurrency,
-    tokenSourcesByChainId,
     blockscoutOffTokenNoteHtml,
     tokenLabel,
     formatFee,
@@ -888,6 +877,5 @@ module.exports = {
     reviewedNetworkProvider,
     EXT_ICON,
     truncateMiddle,
-    isoDate,
+    transactionTimeHtml,
-    timeAgo,
 };

src/popup/views/home.js

@@ -5,8 +5,7 @@ const {
     balanceLinesForAddress,
     unknownableAmount,
     markTrackedTokensNotFetched,
-    isoDate,
+    transactionTimeHtml,
-    timeAgo,
     addressDotHtml,
     txCounterpartyHtml,
     HISTORY_OFF_TEXT,
@@ -31,6 +30,7 @@ const {
     resetSendValidation,
 } = require("./send");
 const { deriveAddressFromXpub } = require("../../shared/wallet");
+const { truncateAmount } = require("../../shared/amountDisplay");
 const { canRemoveAddress } = require("../../shared/walletDelete");
 const {
     walletDefect,
@@ -81,7 +81,7 @@ function renderTotalValue() {
     if (ethBal === null) {
         el.textContent = "unknown (" + nativeCurrency() + ")";
     } else {
-        const ethStr = ethBal.toFixed(4) + " " + nativeCurrency();
+        const ethStr = truncateAmount(addr.balance) + " " + nativeCurrency();
         const ethUsd = ethPrice
             ? " (" + formatUsd(ethBal * ethPrice) + ")"
             : "";
@@ -149,10 +149,11 @@ function renderHomeTxList(ctx) {
         const titleStr = title ? escapeHtml(title) : "";
         const err = tx.isError ? " (failed)" : "";
         const opacity = tx.isError ? " opacity-50" : "";
-        const ago = escapeHtml(timeAgo(tx.timestamp));
-        const iso = escapeHtml(isoDate(tx.timestamp));
         html += `<div class="home-tx-row py-2 border-b border-border-light text-xs cursor-pointer hover:bg-hover${opacity}" data-tx="${i}">`;
-        html += `<div class="flex justify-between"><span class="text-muted" title="${iso}">${ago}</span><span>${dirLabel}${err}</span></div>`;
+        // The time has a line of its own, so a long time or direction label
+        // never pushes the other onto a second line.
+        html += `<div class="text-muted">${transactionTimeHtml(tx.timestamp)}</div>`;
+        html += `<div class="text-right">${dirLabel}${err}</div>`;
         html += txCounterpartyHtml(counterparty, titleStr, amountStr);
         html += `</div>`;
         i++;

src/popup/views/send.js

@@ -10,9 +10,13 @@ const {
     renderAddressHtml,
     attachCopyHandlers,
     goBack,
-    tokenSourcesByChainId,
 } = require("./helpers");
-const { state, currentAddress, currentNetwork } = require("../../shared/state");
+const {
+    state,
+    currentAddress,
+    currentNetwork,
+    tokenSourcesByChainId,
+} = require("../../shared/state");
 let ctx;
 const { getProvider } = require("../../shared/balances");
 const { resolveTokenDecimals } = require("../../shared/approvalAmount");
@@ -20,7 +24,7 @@ const { resolveSymbol } = require("../../shared/tokenList");
 const { isLowHolderCount } = require("../../shared/holders");
 const { isSpoofedSymbol } = require("../../shared/symbolSpoof");
 const {
-    truncateAmountNeverZero,
+    truncateAmount,
     isBelowOneMillionth,
 } = require("../../shared/amountDisplay");
 const {
@@ -235,7 +239,7 @@ function updateSendBalance() {
             addr.balance == null
                 ? "Current balance: unknown (" + nativeCurrency() + ")"
                 : "Current balance: " +
-                  truncateAmountNeverZero(addr.balance) +
+                  truncateAmount(addr.balance) +
                   " " +
                   nativeCurrency();
     } else {
@@ -254,18 +258,15 @@ function updateSendBalance() {
         $("send-balance").textContent =
             bal == null
                 ? "Current balance: unknown (" + symbol + ")"
-                : "Current balance: " +
+                : "Current balance: " + truncateAmount(bal) + " " + symbol;
-                  truncateAmountNeverZero(bal) +
-                  " " +
-                  symbol;
     }
 }
 
 // Fill the amount field with the most the selected holding can send: a
 // token's whole balance (cut to 18 decimal places), or for ETH the exact
 // balance minus the fee reserve the confirmation screen checks against, never
-// the rounded balance the screen shows. Where there is nothing to fill in, a
+// the balance the screen shows, which is cut to four decimals. Where there is
-// flash message says why.
+// nothing to fill in, a flash message says why.
 async function fillMaxAmount() {
     const addr = currentAddress();
     if (!addr) return;

src/popup/views/transactionDetail.js

@@ -10,8 +10,7 @@ const {
     CONTRACT_CREATION_TEXT,
     addressDotHtml,
     escapeHtml,
-    isoDate,
+    transactionTimeHtml,
-    timeAgo,
     renderAddressHtml,
     blockieHtml,
     attachCopyHandlers,
@@ -27,7 +26,7 @@ const { nativeCurrencyByChainId } = require("../../shared/networks");
 const { formatEther, formatUnits } = require("ethers");
 const { log, debugFetch } = require("../../shared/log");
 const { storedSettingIsOn } = require("../../shared/storedSettings");
-const { decodeCalldata } = require("./approval");
+const { decodeCalldata } = require("../../shared/calldataDecoder");
 
 /**
  * Determine a human-readable transaction type string from tx fields.
@@ -204,9 +203,9 @@ function render() {
     );
     loadFullTxDetails(tx.hash, tx.chainId);
 
-    const isoStr = isoDate(tx.timestamp);
+    $("tx-detail-time").innerHTML = transactionTimeHtml(tx.timestamp, {
-    $("tx-detail-time").innerHTML =
+        copyable: true,
-        copyableHtml(isoStr) + " (" + escapeHtml(timeAgo(tx.timestamp)) + ")";
+    });
     $("tx-detail-status").textContent = tx.isError ? "Failed" : "Success";
     showView("transaction");
     attachCopyHandlers("view-transaction");

src/shared/amountDisplay.js

@@ -2,7 +2,7 @@
 // the one exception to it, in one place. Three call sites had grown their own
 // copy of the truncation — the history and balance lists
 // (`src/shared/transactions.js`), the approval screen's ERC-20 amount line
-// (`src/popup/views/approval.js`) and its Uniswap swap detail lines
+// (`src/shared/calldataDecoder.js`) and its Uniswap swap detail lines
 // (`src/shared/uniswap.js`) — and a fix applied to one of them left the other
 // two showing a different number for the same value.
 //

src/shared/calldataDecoder.js

@@ -0,0 +1,155 @@
+// Decode a transaction's calldata into the summary that TxApproval and
+// TransactionDetail show: ERC-20 `approve` and `transfer` calls here, and
+// Uniswap Universal Router calls through uniswap.js. The summary is data; the
+// views turn its addresses into HTML.
+
+const { formatUnits, Interface } = require("ethers");
+const { ERC20_ABI } = require("./constants");
+const { tokenSourcesByChainId } = require("./state");
+const {
+    resolveTokenDecimals,
+    resolveTokenSymbol,
+    unknownDecimalsAmount,
+} = require("./approvalAmount");
+// Four decimals, with the nonzero floor the approval screens hold.
+const { truncateAmountNeverZero } = require("./amountDisplay");
+const uniswap = require("./uniswap");
+
+const erc20Iface = new Interface(ERC20_ABI);
+
+// The amount line for a decoded ERC-20 call. With a known scale it is the
+// token quantity; with `decimals` null it is the base-unit integer with the
+// unknown scale stated, because formatting it with an assumed scale is what
+// showed a 5,000-token transfer as `0.0000`. `raw` is what the status screens
+// carry, `display` is what the approval screen shows.
+function tokenAmountText(rawAmount, decimals, symbol) {
+    if (decimals === null) {
+        const unknown = unknownDecimalsAmount(rawAmount);
+        return { raw: unknown, display: unknown };
+    }
+    const formatted = truncateAmountNeverZero(formatUnits(rawAmount, decimals));
+    return {
+        raw: formatted,
+        display: formatted + (symbol ? " " + symbol : ""),
+    };
+}
+
+// Try to decode calldata sent from `fromAddress` to `toAddress` on the network
+// with chain id `chainId`, using known ABIs.
+// Returns { name, description, details } or null.
+function decodeCalldata(data, toAddress, chainId, fromAddress) {
+    if (!data || data === "0x" || data.length < 10) return null;
+
+    // Where a token's name and scale are looked for, for every decoder below:
+    // what the wallet knows of the tokens on the network with `chainId`, which
+    // need not be the active one. The ERC-20 amount line and the swap's Amount
+    // and Min. received lines resolve the scale the same way, and refuse to
+    // format the same way when it is nowhere.
+    const decimalsSources = tokenSourcesByChainId(chainId);
+
+    // Try ERC-20 (approve / transfer)
+    try {
+        const parsed = erc20Iface.parseTransaction({ data });
+        if (parsed) {
+            const tokenSymbol = resolveTokenSymbol(toAddress, decimalsSources);
+            // null when no source knows this token's scale. It is not
+            // defaulted to 18: an amount formatted with a guessed scale is
+            // the wrong number, and for a token with fewer decimals than the
+            // guess it is the wrong number in the direction that reads as
+            // zero. See tokenAmountText().
+            const tokenDecimals = resolveTokenDecimals(
+                toAddress,
+                decimalsSources,
+            );
+            const contractLabel = tokenSymbol
+                ? tokenSymbol + " (" + toAddress + ")"
+                : toAddress;
+
+            if (parsed.name === "approve") {
+                const spender = parsed.args[0];
+                const rawAmount = parsed.args[1];
+                const maxUint = BigInt(
+                    "0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
+                );
+                const isUnlimited = rawAmount === maxUint;
+                // An unbounded allowance needs no scale to describe, so it is
+                // still named rather than refused.
+                const amount = isUnlimited
+                    ? { raw: "Unlimited", display: "Unlimited" }
+                    : tokenAmountText(rawAmount, tokenDecimals, tokenSymbol);
+
+                return {
+                    name: "Token Approval",
+                    description: tokenSymbol
+                        ? "Approve spending of your " + tokenSymbol
+                        : "Approve spending of an ERC-20 token",
+                    details: [
+                        {
+                            label: "Token",
+                            value: contractLabel,
+                            address: toAddress,
+                            isToken: true,
+                        },
+                        {
+                            label: "Spender",
+                            value: spender,
+                            address: spender,
+                        },
+                        {
+                            label: "Amount",
+                            value: amount.display,
+                            rawValue: amount.raw,
+                        },
+                    ],
+                };
+            }
+
+            if (parsed.name === "transfer") {
+                const to = parsed.args[0];
+                const rawAmount = parsed.args[1];
+                const amount = tokenAmountText(
+                    rawAmount,
+                    tokenDecimals,
+                    tokenSymbol,
+                );
+
+                return {
+                    name: "Token Transfer",
+                    description: tokenSymbol
+                        ? "Transfer " + tokenSymbol
+                        : "Transfer ERC-20 token",
+                    details: [
+                        {
+                            label: "Token",
+                            value: contractLabel,
+                            address: toAddress,
+                            isToken: true,
+                        },
+                        { label: "Recipient", value: to, address: to },
+                        {
+                            label: "Amount",
+                            value: amount.display,
+                            rawValue: amount.raw,
+                        },
+                    ],
+                };
+            }
+        }
+    } catch {
+        // Not ERC-20 — fall through
+    }
+
+    // Try Uniswap Universal Router
+    const routerResult = uniswap.decode(
+        data,
+        toAddress,
+        chainId,
+        decimalsSources,
+        fromAddress,
+    );
+    if (routerResult) return routerResult;
+
+    return null;
+}
+
+module.exports = { decodeCalldata, tokenAmountText };

src/shared/state.js

@@ -22,7 +22,7 @@
 // same thing in the editor is fast feedback in front of the build, not the
 // guarantee.
 
-const { networkById } = require("./networks");
+const { networkById, networkByChainId } = require("./networks");
 const { copyChainSwitchFields } = require("./chainSwitchFields");
 const {
     DEFAULT_STATE,
@@ -125,6 +125,32 @@ function currentNetwork() {
     return networkById(state.networkId);
 }
 
+// What the wallet knows of the tokens on the network with this chain id, or
+// on the active network when no chain id is given, as the `sources` that
+// resolveTokenSymbol() and resolveTokenDecimals() take. A contract address
+// names a token on one network only, and every token balance held is the
+// active network's, so another network gets the tokens tracked on it
+// (state.networkTrackedTokens, see applyChainSwitchFields()) and no balances.
+//
+// The wallets' balances hold what Blockscout reported for each token. So the
+// wallets are returned only while "Use Blockscout" is on.
+function tokenSourcesByChainId(chainId) {
+    const chainIdOrActive = chainId || currentNetwork().chainId;
+    const net = networkByChainId(chainIdOrActive);
+    if (net && net.id === state.networkId) {
+        return {
+            chainId: chainIdOrActive,
+            trackedTokens: state.trackedTokens,
+            wallets: state.useBlockscout ? state.wallets : [],
+        };
+    }
+    return {
+        chainId: chainIdOrActive,
+        trackedTokens: (net && state.networkTrackedTokens[net.id]) || [],
+        wallets: [],
+    };
+}
+
 // `baseline` holds the persisted fields as this page held them when its last
 // loadState() finished, or when its last successful saveState() began.
 // takeStoredNetwork(), takeStoredTrackedTokens() and
@@ -820,5 +846,6 @@ module.exports = {
     loadState,
     currentAddress,
     currentNetwork,
+    tokenSourcesByChainId,
     StateNotLoadedError,
 };

src/shared/wallet.js

@@ -1,7 +1,7 @@
 // Wallet operations: mnemonic generation, HD derivation, signing.
 // All crypto delegated to ethers.js.
 
-const { Mnemonic, HDNodeWallet, Wallet } = require("ethers");
+const { Mnemonic, HDNodeWallet, Wallet, randomBytes } = require("ethers");
 const { DEBUG, DEBUG_MNEMONIC, BIP44_ETH_PATH } = require("./constants");
 
 function generateMnemonic() {
@@ -10,10 +10,7 @@ function generateMnemonic() {
     // settings toggle drives, which would let a user of a release build turn
     // the hardcoded, publicly known test phrase back on for real wallets.
     if (DEBUG) return DEBUG_MNEMONIC;
-    const m = Mnemonic.fromEntropy(
+    return Mnemonic.fromEntropy(randomBytes(16)).phrase;
-        globalThis.crypto.getRandomValues(new Uint8Array(16)),
-    );
-    return m.phrase;
 }
 
 // Every extended key (xprv or xpub) entering the app goes through this.

tests/approvalAmount.test.js

@@ -23,7 +23,7 @@ const {
     resolveTokenDecimals,
     unknownDecimalsAmount,
 } = require("../src/shared/approvalAmount");
-const { decodeCalldata } = require("../src/popup/views/approval");
+const { decodeCalldata } = require("../src/shared/calldataDecoder");
 
 const iface = new Interface(ERC20_ABI);
 

tests/approvalDisplayFloor.test.js

@@ -13,7 +13,7 @@
 // asserted on `rawValue` alongside the displayed line.
 //
 // Both amount paths of that screen are covered: the ERC-20 line decoded by
-// `src/popup/views/approval.js`, and the swap's `Amount` and `Min. received`
+// `src/shared/calldataDecoder.js`, and the swap's `Amount` and `Min. received`
 // lines decoded by `src/shared/uniswap.js`.
 
 globalThis.chrome = {
@@ -23,12 +23,8 @@ globalThis.chrome = {
 const { AbiCoder, Interface } = require("ethers");
 const { ERC20_ABI } = require("../src/shared/constants");
 const { state } = require("../src/shared/state");
-const { decodeCalldata } = require("../src/popup/views/approval");
+const { decodeCalldata } = require("../src/shared/calldataDecoder");
 const uniswap = require("../src/shared/uniswap");
-const {
-    truncateAmount,
-    truncateAmountNeverZero,
-} = require("../src/shared/amountDisplay");
 
 const iface = new Interface(ERC20_ABI);
 
@@ -183,15 +179,4 @@ describe("the four-decimal rule is otherwise unchanged", () => {
     test("a genuine zero still renders as zero", () => {
         expect(amount(transferData(0n), DAI).rawValue).toBe("0.0000");
     });
-
-    // The three truncators now share one module. The floor is a policy of the
-    // approval and confirmation screens only: the history and balance lists
-    // keep plain truncation, because the transaction detail view is the
-    // authoritative record and already shows exact precision.
-    test("the list rule stays unfloored", () => {
-        expect(truncateAmount("0.000000000000000001")).toBe("0.0000");
-        expect(truncateAmountNeverZero("0.000000000000000001")).toBe(
-            "0.000000000000000001",
-        );
-    });
 });

tests/balanceLineEscaping.test.js

@@ -41,13 +41,13 @@ describe("balanceLine", () => {
         // this payload before its id attribute, so an assertion about the
         // rest of the payload would pass on the cap and say nothing about
         // the escape.
-        const html = balanceLine(HOSTILE_SYMBOL, 1, null, null);
+        const html = balanceLine(HOSTILE_SYMBOL, "1", null, null);
         expect(html).not.toContain("<iframe");
         expect(html).toContain("&lt;iframe");
     });
 
     test("caps the symbol before rendering it", () => {
-        const html = balanceLine("A".repeat(4096), 1, null, null);
+        const html = balanceLine("A".repeat(4096), "1", null, null);
         expect(html).toContain("A".repeat(MAX_SYMBOL_LENGTH - 1) + "…");
         expect(html).not.toContain("A".repeat(MAX_SYMBOL_LENGTH + 1));
     });
@@ -55,13 +55,13 @@ describe("balanceLine", () => {
     // The token id lands inside data-token="...", so a quote in it is a
     // way out of the attribute and into a new one.
     test("keeps a quote-bearing token id inside its attribute", () => {
-        const html = balanceLine("TKN", 1, null, '" onclick="alert(1)');
+        const html = balanceLine("TKN", "1", null, '" onclick="alert(1)');
         expect(html).not.toContain('onclick="');
         expect(html).toContain('data-token="&quot; onclick=&quot;alert(1)"');
     });
 
     test("renders an ordinary holding unchanged", () => {
-        const html = balanceLine("USDC", 1.5, null, "0xabc");
+        const html = balanceLine("USDC", "1.5", null, "0xabc");
         expect(html).toContain("<span>USDC</span>");
         expect(html).toContain("<span>1.5000</span>");
         expect(html).toContain('data-token="0xabc"');
@@ -69,7 +69,7 @@ describe("balanceLine", () => {
 
     // formatUsd() writes a value under a cent as "< $0.01".
     test("escapes the USD value along with the symbol", () => {
-        const html = balanceLine("USDC", 0.001, 1, null);
+        const html = balanceLine("USDC", "0.001", 1, null);
         expect(html).toContain("&lt; $0.01");
         expect(html).not.toContain("< $0.01");
     });

tests/balanceTruncation.test.js

@@ -0,0 +1,91 @@
+// The balance lists, Home's ETH line and Send's current balance show a balance
+// as the history rows do (README.md, Amounts): cut to four decimal places,
+// never rounded up (https://git.eeqj.de/sneak/AutistMask/issues/757).
+//
+// Driven through the real popup over a stored profile on Ethereum Mainnet.
+
+const {
+    ADDRESS,
+    bootPopup,
+    cleanupPopup,
+    unversionedValidProfile,
+} = require("./support/popupBoot");
+const { balanceLine } = require("../src/popup/views/helpers");
+
+const USDC = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48";
+
+afterEach(() => {
+    cleanupPopup();
+});
+
+// The quantity cell of a balance row.
+function quantity(row) {
+    return row.match(/<span>([^<]*)<\/span><\/span>/)[1];
+}
+
+// The popup on Home over one address holding `eth` ETH and `usdc` USDC.
+function bootHolding(eth, usdc) {
+    const profile = unversionedValidProfile({
+        trackedTokens: [{ address: USDC, symbol: "USDC", decimals: 6 }],
+    });
+    profile.wallets[0].addresses[0] = {
+        address: ADDRESS,
+        balance: eth,
+        tokenBalances: [
+            { address: USDC, symbol: "USDC", decimals: 6, balance: usdc },
+        ],
+    };
+    return bootPopup(profile);
+}
+
+// The balance row for `token` in Home's wallet list.
+function homeRow(page, token) {
+    return page
+        .node("wallet-list")
+        .innerHTML.split("<div ")
+        .find((row) => row.includes('data-token="' + token + '"'));
+}
+
+describe("balanceLine", () => {
+    test("cuts 0.99996 to 0.9999, never rounding it up to 1.0000", () => {
+        expect(quantity(balanceLine("ETH", "0.99996", null, "ETH"))).toBe(
+            "0.9999",
+        );
+    });
+
+    test("cuts 0.00004 to 0.0000", () => {
+        expect(quantity(balanceLine("USDC", "0.00004", null, USDC))).toBe(
+            "0.0000",
+        );
+    });
+});
+
+describe("Home", () => {
+    test("the ETH line and the balance list read 0.99996 ETH as 0.9999", async () => {
+        const page = await bootHolding("0.99996", "0.00004");
+
+        expect(page.visibleViews()).toEqual(["main"]);
+        expect(page.text("total-value")).toBe("0.9999 ETH");
+        expect(quantity(homeRow(page, "ETH"))).toBe("0.9999");
+    });
+
+    test("the balance list reads 0.00004 USDC as 0.0000", async () => {
+        const page = await bootHolding("0.99996", "0.00004");
+
+        expect(quantity(homeRow(page, USDC.toLowerCase()))).toBe("0.0000");
+    });
+});
+
+describe("Send", () => {
+    test("the current balance reads 0.00004 USDC as 0.0000", async () => {
+        const page = await bootHolding("0.99996", "0.00004");
+        await page.click("btn-main-send");
+        // USDC chosen in the dropdown, as the user does.
+        const dropdown = page.node("send-token");
+        dropdown.value = USDC;
+        for (const fn of dropdown.listeners.change) await fn();
+
+        expect(page.visibleViews()).toEqual(["send"]);
+        expect(page.text("send-balance")).toBe("Current balance: 0.0000 USDC");
+    });
+});

tests/deleteAddress.test.js

@@ -4,8 +4,8 @@
 // the copy is the substance and is tested as such. Two things it must not
 // get wrong: what it takes to get the address back — the app refuses both
 // obvious routes — and what counts as holding something, which is any
-// ERC-20 as well as ETH, at any size, including a balance that rounds to
+// ERC-20 as well as ETH, at any size, including a balance below the four
-// zero at the four decimals the balance lines render. The DOM behaviour
+// decimals the balance lines render. The DOM behaviour
 // around them is driven against the real popup by tests/e2e/run.js.
 
 // helpers.js pulls in state.js, which reads chrome.storage.local at load.
@@ -165,9 +165,9 @@ describe("the balance warning on the removal confirmation", () => {
     });
 
     // The sentence must not assert an amount, because any amount it could
-    // assert has been rounded: "This address holds 0.0000 ETH." is what the
+    // assert has been cut to four decimals: "This address holds 0.0000 ETH." is
-    // rounded form produces for an address that holds real money.
+    // what the cut form produces for an address that holds real money.
-    test("the warning sentence asserts no rounded amount", () => {
+    test("the warning sentence asserts no cut amount", () => {
         for (const addr of [DUST, ETH_ONLY, TOKEN_ONLY]) {
             expect(balanceWarningHtml(addr)).not.toMatch(
                 /holds [\d.]+ (ETH|USDC)/,

tests/e2e/run.js

@@ -829,12 +829,11 @@ test("a common-token quick-pick fills in the contract address (#150)", async (en
     await visible(env.page, "#view-address");
 });
 
-// The native amount as the transaction list writes it (four decimals) and
+// The native amount as the transaction list writes it (cut to four decimals,
-// as the detail screen writes it (full precision). Both are rendered here
+// quantity() below) and as the detail screen writes it (full precision). Both
-// from the fixture rather than read off the screen, so the assertions
+// are rendered here from the fixture rather than read off the screen, so the
-// compare against the wei the stub served.
+// assertions compare against the wei the stub served.
-const NATIVE_ROW_TEXT =
+const NATIVE_ROW_TEXT = quantity(STUB_NATIVE_VALUE_WEI) + " ETH";
-    parseFloat(formatEther(STUB_NATIVE_VALUE_WEI)).toFixed(4) + " ETH";
 const NATIVE_DETAIL_TEXT = formatEther(STUB_NATIVE_VALUE_WEI) + " ETH";
 
 test("the native ETH transaction detail still renders (#151)", async (env) => {
@@ -952,6 +951,71 @@ test("tap-to-copy on the transaction detail screen copies the address (#151)", a
     );
 });
 
+// ------------------------------------------ history row time (#760)
+
+// A Home history row shows the ISO datetime and then the relative age, on a
+// line of its own. Measured at the popup's size: the time line is one line
+// high, and no line of a row is wider than the row or the popup.
+test("a Home history row shows the datetime and the age, one line high, without overflow (#760)", async (env) => {
+    await goHome(env.page);
+    env.routeOpts.seedNativeTransfer = true;
+    const page = await openPopup(env.ctx, env.popupUrl);
+    try {
+        await page.setViewportSize(POPUP_VIEWPORT);
+        await visible(page, "#view-main");
+        await page.waitForFunction(
+            () =>
+                document.querySelectorAll("#home-tx-list .home-tx-row")
+                    .length === 2,
+            null,
+            { timeout: 30000 },
+        );
+        const rows = await page.evaluate(() => {
+            const popupRight = document.body.getBoundingClientRect().right;
+            return [
+                ...document.querySelectorAll("#home-tx-list .home-tx-row"),
+            ].map((row) => {
+                const time = row.firstElementChild;
+                return {
+                    time: time.textContent,
+                    timeHeight: time.getBoundingClientRect().height,
+                    lineHeight: parseFloat(getComputedStyle(time).lineHeight),
+                    overflowingLines: [...row.children].filter(
+                        (line) =>
+                            line.scrollWidth > line.clientWidth ||
+                            line.getBoundingClientRect().right > popupRight,
+                    ).length,
+                };
+            });
+        });
+        console.log("# Home history rows: " + JSON.stringify(rows));
+        for (const row of rows) {
+            assert(
+                /^\d{4}-\d\d-\d\dT\d\d:\d\d:\d\d(Z|[+-]\d\d:\d\d) \(\d+ \w+ ago\)$/.test(
+                    row.time,
+                ),
+                "the time line is not the ISO datetime and then the age: " +
+                    JSON.stringify(row.time),
+            );
+            assert(
+                row.timeHeight === row.lineHeight,
+                "the time line is " +
+                    row.timeHeight +
+                    "px high, not one line of " +
+                    row.lineHeight +
+                    "px",
+            );
+            assert(
+                row.overflowingLines === 0,
+                row.overflowingLines + " line(s) of a row overflow it",
+            );
+        }
+    } finally {
+        env.routeOpts.seedNativeTransfer = false;
+        await page.close();
+    }
+});
+
 // ------------------------- the last of the #150 and #151 items (#295)
 //
 // Add Token's confirm button, TransactionDetail opened from the token screen
@@ -2724,10 +2788,11 @@ async function goToConfirm(page, send) {
     await assertAddressesFit(page, "the confirmation screen");
 }
 
-// A balance as the main view renders it: balanceLinesForAddress() writes
+// An amount in wei as the main view's balance lines and the transaction list
-// every quantity with four decimal places.
+// write it: cut to four decimal places, never rounded, as feeEth() does.
 function quantity(wei) {
-    return parseFloat(formatEther(wei)).toFixed(4);
+    const [whole, frac = ""] = formatEther(wei).split(".");
+    return whole + "." + (frac + "0000").slice(0, 4);
 }
 
 // Wait on the main view until a changed balance fixture has been picked up.

tests/fabricatedDecimals.test.js

@@ -47,7 +47,7 @@ const { fetchTokenBalances } = require("../src/shared/balances");
 const { debugFetch } = require("../src/shared/log");
 const { state } = require("../src/shared/state");
 const { unknownDecimalsAmount } = require("../src/shared/approvalAmount");
-const { decodeCalldata } = require("../src/popup/views/approval");
+const { decodeCalldata } = require("../src/shared/calldataDecoder");
 const { TOKEN_BY_ADDRESS } = require("../src/shared/tokenList");
 
 const HOLDER = "0x" + "a".repeat(40);

tests/packaging.test.js

@@ -1,4 +1,5 @@
-// The release archives: the zip container, and the self-containment rule.
+// The release archives: the zip container, the self-containment rule, and the
+// digest format in release/SHA256SUMS.
 //
 // script/package produces one archive per browser and script/lib/package.js
 // decides what goes in it. The trap that rule exists for is real and specific:
@@ -11,12 +12,14 @@
 // So the packager resolves every reference in the manifest and in every HTML
 // document, and fails on any that leaves the extension root. These are the
 // cases for that, plus the archive format itself — new code, and the thing the
-// artifact is made of.
+// artifact is made of. One more case checks the digest format in
+// release/SHA256SUMS.
 
 const {
     checkSelfContained,
     htmlReferences,
     manifestReferences,
+    sha256,
 } = require("../script/lib/package");
 const { readZip, writeZip } = require("../script/lib/zip");
 
@@ -142,6 +145,14 @@ describe("archive self-containment", () => {
     });
 });
 
+// release/SHA256SUMS is checked with `sha256sum -c`, which needs the digest
+// as bare lowercase hex. The expected value is the FIPS 180-2 digest of "abc".
+test("sha256 prints the digest as sha256sum does", () => {
+    expect(sha256(Buffer.from("abc"))).toBe(
+        "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad",
+    );
+});
+
 describe("the zip container", () => {
     const files = [
         { name: "manifest.json", data: Buffer.from('{"a":1}') },

tests/resolveTokenSymbol.test.js

@@ -22,7 +22,7 @@ const { Interface } = require("ethers");
 const { ERC20_ABI } = require("../src/shared/constants");
 const { state } = require("../src/shared/state");
 const { resolveTokenSymbol } = require("../src/shared/approvalAmount");
-const { decodeCalldata } = require("../src/popup/views/approval");
+const { decodeCalldata } = require("../src/shared/calldataDecoder");
 
 const iface = new Interface(ERC20_ABI);
 

tests/sendDisplayFloor.test.js

@@ -6,8 +6,10 @@
 // balances and the fee were each cut to six decimal places, a rule of their
 // own, and a token holding cut to zero was dropped, while the approval screen
 // showed the same fee through src/shared/amountDisplay.js with the nonzero
-// floor. The balances are now stored exactly, every nonzero token holding
+// floor. The balances are now stored exactly, and every nonzero token holding
-// kept, and the screens show them and the fee through that helper.
+// is kept. The fee lines show the fee through that helper with the floor. The
+// balance lines cut a balance to four decimals, as the balance lists do, so a
+// balance below 0.0001 reads 0.0000.
 //
 // Driven through the real refreshBalances(), Send screen, confirmation screen
 // and approval screen, with only the node, the explorer and the DOM stubbed: a
@@ -278,21 +280,22 @@ beforeEach(() => {
     mockNode.feeData = { maxFeePerGas: 1n, gasPrice: 1n };
 });
 
-describe("an ETH balance below 0.000001 never renders as zero", () => {
+describe("an ETH balance below 0.0001 reads 0.0000", () => {
     test("on the Send screen", async () => {
         await refreshWith(HALF_MICRO_ETH);
         state.selectedToken = "ETH";
         send.updateSendBalance();
-        expect(text("send-balance")).toBe("Current balance: 0.0000005 ETH");
+        expect(text("send-balance")).toBe("Current balance: 0.0000 ETH");
+        expect(state.wallets[0].addresses[0].balance).toBe("0.0000005");
     });
 
     test("on the confirmation screen", async () => {
         await refreshWith(HALF_MICRO_ETH);
         await confirmSend("0.0000001");
-        expect(text("confirm-balance")).toBe("0.0000005 ETH");
+        expect(text("confirm-balance")).toBe("0.0000 ETH");
     });
 
-    test("while a balance above the floor keeps four decimals", async () => {
+    test("while a larger balance is cut to four decimals", async () => {
         await refreshWith(1234567890000000000n);
         await confirmSend("0.1");
         expect(text("confirm-balance")).toBe("1.2345 ETH");
@@ -302,7 +305,7 @@ describe("an ETH balance below 0.000001 never renders as zero", () => {
 // A token the user tracks stays on the balance list when the explorer's row is
 // dropped, so a holding of it below 0.000001 reached these screens as zero, and
 // the send was checked against zero.
-describe("a tracked token holding below 0.000001 never renders as zero", () => {
+describe("a tracked token holding below 0.000001 reads 0.0000", () => {
     beforeEach(() => {
         state.trackedTokens = [
             { address: TOKEN, symbol: "TOK", name: "Token", decimals: 18 },
@@ -313,13 +316,17 @@ describe("a tracked token holding below 0.000001 never renders as zero", () => {
         await refreshWith(10n ** 18n, [tokenRow(HALF_MICRO_ETH)]);
         state.selectedToken = TOKEN;
         send.updateSendBalance();
-        expect(text("send-balance")).toBe("Current balance: 0.0000005 TOK");
+        expect(text("send-balance")).toBe("Current balance: 0.0000 TOK");
+        const stored = state.wallets[0].addresses[0].tokenBalances.find(
+            (t) => t.address === TOKEN,
+        );
+        expect(stored.balance).toBe("0.0000005");
     });
 
     test("on the confirmation screen, which checks the send against it", async () => {
         await refreshWith(10n ** 18n, [tokenRow(HALF_MICRO_ETH)]);
         await confirmSend("0.0000005", TOKEN);
-        expect(text("confirm-balance")).toBe("0.0000005 TOK");
+        expect(text("confirm-balance")).toBe("0.0000 TOK");
         expect(errors()).toBe("");
         expect(balanceError()).toBe("");
         await confirmSend("0.0000006", TOKEN);
@@ -347,11 +354,9 @@ describe("a tracked token holding below 0.000001 never renders as zero", () => {
         await refreshWith(10n ** 18n, [tokenRow(1n, { decimals: "24" })]);
         state.selectedToken = TOKEN;
         send.updateSendBalance();
-        expect(text("send-balance")).toBe(
+        expect(text("send-balance")).toBe("Current balance: 0.0000 TOK");
-            "Current balance: 0.000000000000000000000001 TOK",
-        );
         await confirmSend("0.000000000000000001", TOKEN);
-        expect(text("confirm-balance")).toBe("0.000000000000000000000001 TOK");
+        expect(text("confirm-balance")).toBe("0.0000 TOK");
         expect(balanceError()).toContain(
             "Your TOK balance does not cover this amount.",
         );
@@ -363,20 +368,20 @@ describe("a tracked token holding below 0.000001 never renders as zero", () => {
 // selected while its own screen is open: after sending 2 of a 2.0000003
 // holding, the user is back on that screen, and Send read the missing row as
 // zero.
-describe("an untracked token holding below 0.000001 never renders as zero", () => {
+describe("an untracked token holding below 0.000001 reads 0.0000", () => {
     const row = () => tokenRow(HALF_MICRO_ETH, { holders_count: "50000" });
 
     test("on the Send screen", async () => {
         await refreshWith(10n ** 18n, [row()]);
         state.selectedToken = TOKEN;
         send.updateSendBalance();
-        expect(text("send-balance")).toBe("Current balance: 0.0000005 TOK");
+        expect(text("send-balance")).toBe("Current balance: 0.0000 TOK");
     });
 
     test("on the confirmation screen, which checks the send against it", async () => {
         await refreshWith(10n ** 18n, [row()]);
         await confirmSend("0.0000005", TOKEN);
-        expect(text("confirm-balance")).toBe("0.0000005 TOK");
+        expect(text("confirm-balance")).toBe("0.0000 TOK");
         expect(errors()).toBe("");
         expect(balanceError()).toBe("");
         await confirmSend("0.0000006", TOKEN);

tests/timestampDisplay.test.js

@@ -1,15 +1,14 @@
-// A transaction's time is written by isoDate() and timeAgo() in
+// A transaction's time shows the ISO datetime and the relative age on every
-// src/popup/views/helpers.js on every screen that shows one (README, Amounts;
+// screen that shows one (README, Amounts). Home, AddressDetail and AddressToken
-// https://git.eeqj.de/sneak/AutistMask/issues/168). AddressDetail and
+// used to show only the age, with the datetime as a tooltip
-// AddressToken used to define their own copies, so a fix to the shared pair
+// (https://git.eeqj.de/sneak/AutistMask/issues/760).
-// would not have reached them.
 //
-// The pair is replaced before the views are loaded, because a view takes it
+// The views run against a minimal DOM stub, as in
-// when it loads. A view that writes the time with a copy of its own shows the
+// tests/historyAfterNetworkSwitch.test.js, and over
-// real time instead of the replacement.
+// tests/support/storageStub.js.
-//
+
-// Driven against a minimal DOM stub in the shape
+const { makeStorageStub } = require("./support/storageStub");
-// tests/contractCreation.test.js uses.
+const { STATE_SCHEMA_VERSION } = require("../src/shared/stateSchema");
 
 jest.mock("../src/shared/log", () => ({
     log: {
@@ -26,33 +25,78 @@ jest.mock("../src/shared/log", () => ({
 }));
 
 // The history lists ask the explorer for their transactions and resolve ENS
-// names for them; here the explorer answers with mockHistory and no name
+// names for them; here the explorer answers with mockHistory() and no name
 // resolves.
-let mockHistory = [];
 jest.mock("../src/shared/transactions", () => ({
     ...jest.requireActual("../src/shared/transactions"),
-    fetchRecentTransactions: async () => mockHistory,
+    fetchRecentTransactions: async () => mockHistory(),
 }));
 jest.mock("../src/shared/ens", () => ({
     ...jest.requireActual("../src/shared/ens"),
     resolveEnsNames: async () => new Map(),
 }));
 
-globalThis.chrome = {
+const { state, loadState } = require("../src/shared/state");
-    storage: { local: { get: async () => ({}), set: async () => {} } },
+const home = require("../src/popup/views/home");
-};
-
-const helpers = require("../src/popup/views/helpers");
-jest.spyOn(helpers, "isoDate").mockReturnValue("SHARED-ISO-DATE");
-jest.spyOn(helpers, "timeAgo").mockReturnValue("SHARED-TIME-AGO");
-
-const { state } = require("../src/shared/state");
 const addressDetail = require("../src/popup/views/addressDetail");
 const addressToken = require("../src/popup/views/addressToken");
 const transactionDetail = require("../src/popup/views/transactionDetail");
 
 const FROM = "0x0000000000000000000000000000000000000a11";
 const RECIPIENT = "0x66133E8ea0f5D1d612D2502a968757D1048c214a";
+const TIMESTAMP = 1790000000;
+// TIMESTAMP as shown with "UTC Timestamps" on, three hours after it.
+const SHOWN_TIME = "2026-09-21T14:13:20Z (3 hours ago)";
+
+// A profile on Ethereum Mainnet with one address, "Use Blockscout" and "UTC
+// Timestamps" on.
+function profile() {
+    return {
+        schemaVersion: STATE_SCHEMA_VERSION,
+        hasWallet: true,
+        wallets: [
+            {
+                type: "hd",
+                name: "Main",
+                xpub: "xpub-main",
+                encryptedSecret: "encrypted-secret",
+                nextIndex: 1,
+                addresses: [
+                    { address: FROM, balance: "1.0", tokenBalances: [] },
+                ],
+            },
+        ],
+        activeAddress: FROM,
+        networkId: "mainnet",
+        rpcUrl: "https://ethereum-rpc.publicnode.com",
+        blockscoutUrl: "https://eth.blockscout.com/api/v2",
+        useBlockscout: true,
+        utcTimestamps: true,
+    };
+}
+
+// A transfer of ETH from FROM, as Blockscout answers it.
+function mockHistory() {
+    return [
+        {
+            hash: "0x85215772ed26ea8b39c2b3b18779030487efbe0b5fd7e882592b2f62b837be84",
+            blockNumber: 1,
+            from: FROM,
+            to: RECIPIENT,
+            value: "0.0000",
+            exactValue: "0.0",
+            rawAmount: "0",
+            rawUnit: "wei",
+            symbol: "ETH",
+            timestamp: TIMESTAMP,
+            isError: false,
+            directionLabel: "Sent",
+            direction: "sent",
+            contractAddress: null,
+            chainId: "0x1",
+        },
+    ];
+}
 
 function makeElement(id) {
     const el = {
@@ -90,6 +134,7 @@ function makeDocument() {
             return els.get(id);
         },
         createElement: () => makeElement("created"),
+        addEventListener: () => {},
         body: { prepend: () => {} },
     };
 }
@@ -98,64 +143,58 @@ function node(id) {
     return globalThis.document.getElementById(id);
 }
 
-// A transaction FROM sent, as the history lists hold it.
+// Lets every promise that is not held open settle.
-function historyTx() {
+function settle() {
-    return {
+    return new Promise((resolve) => setTimeout(resolve, 0));
-        hash: "0x85215772ed26ea8b39c2b3b18779030487efbe0b5fd7e882592b2f62b837be84",
-        from: FROM,
-        to: RECIPIENT,
-        value: "0.0000",
-        exactValue: "0.0",
-        rawAmount: "0",
-        rawUnit: "wei",
-        symbol: "ETH",
-        timestamp: 1790000000,
-        isError: false,
-        directionLabel: "Sent",
-        direction: "sent",
-        contractAddress: null,
-    };
 }
 
-beforeEach(() => {
+beforeEach(async () => {
+    const storage = makeStorageStub({ autistmask: profile() });
+    globalThis.chrome = {
+        storage: { local: storage.local, onChanged: storage.onChanged },
+    };
     globalThis.document = makeDocument();
     globalThis.window = { location: { search: "" } };
-    state.wallets = [
+    jest.spyOn(Date, "now").mockReturnValue((TIMESTAMP + 3 * 3600) * 1000);
-        {
+    await loadState();
-            name: "Main",
-            type: "key",
-            addresses: [{ address: FROM, balance: "0.0000" }],
-        },
-    ];
-    state.trackedTokens = [];
-    state.viewData = {};
     state.viewStack = [];
-    state.currentView = null;
     state.selectedWallet = 0;
     state.selectedAddress = 0;
     state.selectedToken = "ETH";
-    // The history is Blockscout's.
+    const ctx = { pageClosed: new AbortController().signal };
-    state.useBlockscout = true;
+    addressDetail.init(ctx);
+    addressToken.init(ctx);
+});
+
+afterEach(() => {
+    jest.restoreAllMocks();
+    delete globalThis.chrome;
+    delete globalThis.document;
+    delete globalThis.window;
 });
 
 describe.each([
+    [
+        "Home",
+        "home-tx-list",
+        () => home.render({ pageClosed: new AbortController().signal }),
+    ],
     ["AddressDetail", "tx-list", () => addressDetail.show()],
     ["AddressToken", "address-token-tx-list", () => addressToken.show()],
 ])("a transaction history row on %s", (_name, listId, open) => {
-    test("shows the time written by the shared isoDate() and timeAgo()", async () => {
+    test("shows the ISO datetime and then the relative age", async () => {
-        mockHistory = [historyTx()];
         open();
         // The list is drawn once the history has been fetched.
-        await new Promise((resolve) => setTimeout(resolve, 0));
+        for (let i = 0; i < 10; i++) await settle();
         const html = node(listId).innerHTML;
-        expect(html).toContain('title="SHARED-ISO-DATE"');
+        expect(html).toContain(">" + SHOWN_TIME + "<");
-        expect(html).toContain(">SHARED-TIME-AGO<");
+        expect(html).not.toContain("title=");
     });
 });
 
-test("the transaction detail view shows the time written by the shared isoDate() and timeAgo()", () => {
+test("the transaction detail view shows the ISO datetime, copyable, and then the relative age", () => {
-    transactionDetail.show(historyTx());
+    transactionDetail.show(mockHistory()[0]);
     const html = node("tx-detail-time").innerHTML;
-    expect(html).toContain("SHARED-ISO-DATE");
+    expect(html).toContain('data-copy="2026-09-21T14:13:20Z"');
-    expect(html).toContain("(SHARED-TIME-AGO)");
+    expect(html).toContain(">2026-09-21T14:13:20Z</span> (3 hours ago)");
 });

tests/transactions.test.js

@@ -1361,6 +1361,31 @@ describe("fetchRecentTransactions merge and dedup", () => {
         expect(txs[0].holders).toBe(3500000);
     });
 
+    // README.md, Amounts: a history row cuts to four decimals, with no floor.
+    test("a token transfer below 0.0001 reads 0.0000", async () => {
+        respondWith(
+            [],
+            [
+                {
+                    transaction_hash: "0x" + "4".repeat(64),
+                    block_number: 21000040,
+                    timestamp: TS,
+                    from: { hash: ORDINARY_PEER },
+                    to: { hash: VICTIM },
+                    total: { value: "40", decimals: "6" },
+                    token: {
+                        symbol: "USDC",
+                        address_hash: USDC_CONTRACT,
+                        holders_count: "3500000",
+                    },
+                },
+            ],
+        );
+
+        const txs = await fetchRecentTransactions(VICTIM, BLOCKSCOUT, "0x1");
+        expect(txs[0].value).toBe("0.0000");
+    });
+
     test("two transfers of the same token in one transaction collapse to one entry", async () => {
         const hash = "0x" + "3".repeat(64);
         const leg = (value) => ({

tests/uniswapRouterAddress.test.js

@@ -47,7 +47,7 @@ globalThis.chrome = {
 const { state } = require("../src/shared/state");
 const { fetchRecentTransactions } = require("../src/shared/transactions");
 const approval = require("../src/popup/views/approval");
-const { decodeCalldata } = approval;
+const { decodeCalldata } = require("../src/shared/calldataDecoder");
 const transactionDetail = require("../src/popup/views/transactionDetail");
 
 const MAINNET = "0x1";

tests/uniswapUnknownDecimals.test.js

@@ -18,7 +18,7 @@ globalThis.chrome = {
 const { AbiCoder, Interface } = require("ethers");
 const { state } = require("../src/shared/state");
 const { unknownDecimalsAmount } = require("../src/shared/approvalAmount");
-const { decodeCalldata } = require("../src/popup/views/approval");
+const { decodeCalldata } = require("../src/shared/calldataDecoder");
 
 const ROUTER = "0x66a9893cc07d91d95644aedd05d03f95e1dba8af";
 const RECIPIENT = "0xC0FfEE0000000000000000000000000000c0fFEe";

tests/unknownScaleDisplay.test.js

@@ -96,7 +96,7 @@ afterEach(() => {
 describe("balanceLine", () => {
     test("an unknown quantity and a zero one render differently", () => {
         const unknown = balanceLine("NOVEL", null, null, NOVEL);
-        const zero = balanceLine("NOVEL", 0, null, NOVEL);
+        const zero = balanceLine("NOVEL", "0", null, NOVEL);
         expect(unknown).not.toBe(zero);
         expect(quantities(unknown)).toEqual(["NOVEL", "quantity unknown"]);
         expect(quantities(zero)).toEqual(["NOVEL", "0.0000"]);
@@ -105,7 +105,7 @@ describe("balanceLine", () => {
     test("an unknown quantity produces no fiat figure, a zero one does", () => {
         prices[NOVEL] = 3;
         const unknown = balanceLine("NOVEL", null, 3, NOVEL);
-        const zero = balanceLine("NOVEL", 0, 3, NOVEL);
+        const zero = balanceLine("NOVEL", "0", 3, NOVEL);
         // A price times an unknown quantity is not $0.00: that is the same
         // claim of "nothing here" the quantity cell just refused to make.
         expect(unknown).toContain(